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oblong woodsia, rusty cliff fern, rusty woodsia, woodsie de l'île d'elbe

smooth cliff fern, smooth woodsia, woodsie glabre

Stems

compact, erect to ascending, with abundant persistent petiole bases of ± equal length;

scales uniformly brown, lanceolate.

compact, erect to ascending, with cluster of persistent petiole bases of ± equal length;

scales uniformly brown, lanceolate.

Leaves

4.5–25 × 1.2–3.5 cm.

3.5–15 × 0.5–1.2 cm.

Petiole

usually brown or dark purple when mature, articulate above base at swollen node, relatively brittle and easily shattered.

green or straw-colored throughout, articulate above base at swollen node, somewhat pliable and resistant to shattering.

Blade

narrowly lanceolate, usually 2-pinnate proximally, lacking glands, never viscid;

rachis usually with abundant hairs and scales.

linear to linear-lanceolate, pinnate-pinnatifid proximally, glabrous or with occasional sessile glands, never viscid;

rachis glabrous.

Pinnae

ovate-lanceolate to deltate, longer than wide, abruptly tapered to a rounded or broadly acute apex;

largest pinnae with 4–9 pairs of pinnules;

abaxial surface with mixture of hairs and linear-lanceolate scales, adaxial surface with multicellular hairs concentrated along midrib.

Indusia

of narrow, hairlike segments, these uniseriate throughout, composed of cells many times longer than wide, usually surpassing mature sporangia.

of narrow hairlike segments, these uniseriate throughout, composed of cells many times longer than wide, usually surpassing mature sporangia.

Spores

averaging 39–46 µm. 2n = 82.

averaging 39–45 µm. 2n = 78.

Pinnules

entire or crenate, rarely shallowly lobed;

margins nonlustrous, thin, ciliate with multicellular hairs, lacking translucent projections.

entire or broadly crenate;

margins nonlustrous, thin, lacking cilia or translucent projections.

Vein

tips frequently enlarged to form whitish hydathodes visible adaxially.

tips slightly (if at all) enlarged, barely visible adaxially.

Proximal

pinnae fan-shaped, wider than long;

distal pinnae ovate-lanceolate, longer than wide, abruptly tapered to a rounded or broadly acute apex;

largest pinnae with 1–3 pairs of pinnules, abaxial and adaxial surfaces glabrous.

Woodsia ilvensis

Woodsia glabella

Phenology Sporulating summer–early fall. Sporulating summer–early fall.
Habitat Cliffs and rocky slopes, found on variety of substrates including serpentine Shaded cracks and ledges on cliffs, mostly calcareous rocks, especially limestone
Elevation 0–1500 m (0–4900 ft) 0–1500 m (0–4900 ft)
Distribution
from FNA
AK; CT; IA; IL; MA; MD; ME; MI; MN; NC; NH; NJ; NY; OH; PA; RI; VA; VT; WI; WV; AB; BC; MB; NB; NF; NS; NT; ON; QC; SK; YT; Greenland; n Eurasia
[WildflowerSearch map]
[BONAP county map]
from FNA
AK; ME; MN; NH; NY; VT; AB; BC; MB; NB; NF; NS; NT; ON; QC; SK; YT; Greenland; n Eurasia
[WildflowerSearch map]
[BONAP county map]
Discussion

Although generally separable by the characters given in the key, shade forms of Woodsia ilvensis with a reduced number of scales and hairs are occasionally misidentified as W. alpina. The morphologic distinctions between these species are further blurred by natural hybridization, which produces the intermediate triploid known as W. × gracilis. Some of the best characters for distinguishing these taxa are spore size and morphology. Spores average less than 46 µm in W. ilvensis, more than 46 µm in W. alpina, and are malformed and abortive in W. × gracilis. Woodsia ilvensis also hybridizes with W. oregana subsp. cathcartiana to form the sterile triploid W. × abbeae (F. S. Wagner 1987).

(Discussion copyrighted by Flora of North America; reprinted with permission.)

Woodsia glabella is a well-marked species occasionally confused with narrow, glabrescent forms of W. alpina and W. oregana subsp. oregana. These taxa are readily distinguished from W. glabella by their petioles, which are reddish brown or dark purple near the base.

(Discussion copyrighted by Flora of North America; reprinted with permission.)

Source FNA vol. 2. FNA vol. 2.
Parent taxa Dryopteridaceae > Woodsia Dryopteridaceae > Woodsia
Sibling taxa
W. alpina, W. cochisensis, W. glabella, W. neomexicana, W. obtusa, W. oregana, W. phillipsii, W. plummerae, W. scopulina
W. alpina, W. cochisensis, W. ilvensis, W. neomexicana, W. obtusa, W. oregana, W. phillipsii, W. plummerae, W. scopulina
Synonyms Acrostichum ilvense W. alpina var. glabella, W. hyperborea var. glabella
Name authority (Linnaeus) R. Brown: Trans. Linn. Soc. London, Bot. 11: 173. (1813) R. Brown ex Richardson: in Franklin, Narr. Journey Polar Sea 754. (1823)
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